1. Field of the Invention
The invention relates generally to apparatus for supporting a metal plate in a water table for use with metal cutting machines for cutting parts from the metal plate and more particularly to trays having removable support bars which can be positioned according to the shapes and sizes of the parts which are to be cut from a metal plate.
2. Description of the Prior Art
When cutting a metal plate by either plasma arc cutting or oxy fuel cutting, it is advantageous to immerse the plate in a water bath or position it above the surface of a water bath so that the final part and large skeletal remains are supported above the water bath and the swarf, the scrap and small parts fall into the water bath. When cutting with a plasma arc, the metal plate is grounded to complete the plasma arc transfer process. Grounding the metal plate also enhances the quality of parts cut from the plate and increases operator safety.
Water tables for use with cutting machines are disclosed in U.S. Pat. Nos. 4,162,060 and 4,453,702 and the disclosures thereof are incorporated herein by reference. Those water tables include a plurality of tiltable frames located in open-topped tanks and each frame includes bars which support metal plates to be cut. U.S. Pat. No. 4,673,103 is directed to plate supports in the form of equilateral pyramids which are individually positioned on a cutting surface in accordance with the shape and size of the finished parts which are to be cut from the plate. U.S. Pat. No. 4,986,515 discloses a water table having a support arrangement including intermediate plate support members positioned above a frame which are lowered to contact the upper surface of the metal plate during cutting. Control means move the plate support members relative to the cutting path of the cutting machine. Each of the moveable plate support members is mounted on a cantilever arm and has an electromagnet which contacts the upper surface of a metal plate while it is cut.